EU VAT guide

GLOBAL_MAX_CONCURRENT_REQ VIES error

GLOBAL_MAX_CONCURRENT_REQ means the VIES service is receiving too many concurrent requests globally.

Meaning

This is a traffic-limit response from the VIES side. It does not tell you whether the VAT number is valid or invalid.

High-volume tools should slow down, queue checks, and retry later instead of increasing concurrency.

For API integrations

Treat this error as retryable and store it as an unavailable status until a later validation succeeds or fails.

Avoid exposing this as a customer data issue; it is an upstream capacity condition.

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Related VIES guides

Check a VAT number

You can paste the full VAT ID with country prefix, or choose the country and enter the local number.